Textile crimping



N v. 21, 196 A. M. KEEL ETAL TEXTILE CRIMPING Filed Jan. 22, 1965' FIG- I FIG-3 L Em m AM N M m PW T N T wa A LI M D FIG- 4 United States Patent Ofiflce Patented Nov. 21, 1967 3,353,222 TEXTHE CRHVIPING Alvin M. Keel and Daniel ll. Saxon, Kingsport, Tenn, as-

signors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Fiied Jan. 22, 196$, Ser. No. 427,408 3 Claims. (Cl. 1966) The present invention relates to the crimping of textile fibers. In one of its more specific aspects, this invention relates to an improved apparatus for the crimping of textile fibers.

In the manufacture of certain articles of commerce from textile fibers, it is frequently necessary of desirable to crimp the textile fibers in order that the fibers may have the structure needed for the particular article which is to be produced. Articles of commerce which might require the fibers to be crimped would include cigarette filter tow, fabric yarns, and the like.

A process frequently used at the present for crimping employs an apparatus known in the trade as a stuffing box crimper. The stuffing box crimper has a chamber or stufling box in which the actual crimping of the fibers is accomplished. The chamber or stuffing box is provided at one end with a gate or clapper door which restricts the passage of fibers through the chamber. The gate is hinged so that it can be swung open and shut by a suitable actuator in order that the flow of fiber is restricted in the amount necessary to produce the desired number of crimps per inch of fiber length.

However, the usage of a hinged gate may result in the hinge becoming a snag point in the crimping operation. The hinge may non-uniformly restrict the flow of fiber, thereby causing a non-uniform number of crimps per inch of fiber length. The hinged gate may also be relatively stiff, causing it to close at a comparatively sharp angle with respect to the axis of the textile fiber to be crimped. The sharp angle of closure may cause a too abrupt restriction of fiber flow, thereby producing non-uniformly crimped fibers.

One object of our invention is the improvement of crimp uniformity of textile fibers. Another object of our invention is the development of an improved and more effective apparatus for the crimping of textile fibers. Other objects of our invention will appear herein.

We have discovered that if a non-hinged gate is employed on the crimper apparatus, the degree of crimp uniformity is greatly superior to that obtained by using the conventional hinged gate crimper apparatus.

The accompanying drawing and explanation thereof will serve to more fully explain the improved apparatus and variations thereon of our invention. However, it is to be understood that the following variations of our invention are not all inclusive, and other related structures and modifications of the embodiments described will be within the scope of this invention.

FIGURE 1 is a crosssectional view of a stufling box crimper provided with one embodiment of the nonhinged gate of our invention. The textile fiber 1 is forced into the stuffing box by action of the pair of rolls 2. The stufiiing box is composed of a side plate 3 and scraper blades 4 and 6 which are attached to the machine frame 5 by any suitable securing means. The scraper blade 6 is integral with the clapper door or gate 7 and, as shown in the drawings, is of single piece construction. The extreme right end (as seen from the direction of FIGURE 1) of gate 7 is attached to an actuator 8 by means of a clevis arrangement 9. The actuator serves the purpose of depressing and releasing the gate 7 in order to obtain the desired degree of crimp uniformity. In FIGURE 1, the gate 7 is at the position when no force is being applied to it by actuator 8, when fibers to be crimped have not as yet entered the stufliing box.

FIGURE 1 also shows the clapper door or gate 10 at the position when the actuator 8 has forced the gate down to a predetermined degree and the fibers are actually being crimped. The gate does not move continually up and down, but instead it remains in a constant depressed position until the entire particular crimping operation is completed. Then it returns to position 7.

The gate is not depressed so as to bring it in contact with the floor of the stuffing box. The crimping operation is a continual one, as fibers are always moving in to and out of the stufiing box. Therefore, there must be sufiicient clearance under the gate to allow the crimped fibers to pass out.

FIGURES 2, 3, and 4 represent other Variations which are suitable for the gate to have. FIGURE 2 shows a single piece scraper blade 6 integral with the gate 11. In this variation, the clevis arrangement 9 is positioned to apply force near the middle of gate 11 rather than at the end as in FIGURE 1. Thus, the gate has an overhand or tall 12. When force is applied, the gate assumes the position of 13.

Another design of our non-hinged gate is shown by FIGURE 3. Here the scraper blade 6, gate 14, and clevis 9 assume the same relative positions as in FIGURE 1. However, the gate 14 is of shorter length than that of FIGURE 1, and the longitudinal cross-section of the gate varies from point to point. The depressed gate is shown by 15.

FIGURE 4 shows still another variation that the gate may take. In this configuration, the scraper blade 6 has been lengthened so that it is integral with both ends of the gate 16. The clevis arangement 9 protrudes through a suitable opening in the approximate center of scraper blade 6 and applies force to gate 16 at that point. Number 17 shows the shape and position of the gate when force is being applied to it. This embodiment is, of course, restricted to only relatively small deflections caused by the elastic elongation of gate portion 16 and the deflection of the free end of scrapper blade 6. Therefore, the embodiment illustrated in FIGURE 4 is primarily intended for use where only a small restriction in the exit opening of the stuffing box is required such as when the gate 16 is closely adjacent to a stutfing box scraper blade 4.

It will be apparent that the non-uniformity of the beam used for the gate may be made such that upon the application of a depressing force it will approximate any desired curvature. Such a non-hinged gate will assume a gentle curve with no snag points or abrupt changes in inclination relative to the flow path of the textile fibers being crimped. Hence, crimp uniformity is greatly improved due to the hyperbolic type deflection of the gate when in operation.

However, the design of the crimper gate must be such that the yield stress of the particular material from which it is made will not be exceeded. If said yield stress were exceeded, the gate would take a permanent set and would 'not return to its original position when the force applied by the actuator is reduced to Zero.

The clapper door or gate may be made of any material, provided that such material has the proper friction and wear properties when used in the crimping of yarn. We have found that any hardenable spring alloy which is a non-carbon steel may be successfully employed in the present invention. The material is desirably non-carbon type so as to eliminate corrosion problems which arise with carbon steel. Especially satisfactory results have been obtained using a crimper gate made of stainless steel and one made of a beryllium-copper alloy.

The non-hinged gate of our invention can be employed in the crimping of any fiber, both synthetic and natural, that can normally be crimped in a conventional stuffing box crimper. Examples of such fibers would include the cellulosic fibers, such as cellulose acetate; polyesters; polyolefins; acrylic fibers; polyamides; wool; and like fibers.

As for specific combinations of gate material and fiber, we have found many suitable combinations. For example, for polyester fiber, a stainless steel gate gives very satisfactory results. Examples of other combinations giving good results are polyolefins-stainless steel; cellulose acetatean alloy of beryllium and copper; acrylicsboth stainless steel and the copper-beryllium alloy will function properly here; and wool-stainless steel.

The actuator may be an air cylinder, bellows, diaphragm, or any other suitable actuating device. Pressure from the actuator forces the gate down to a degree previously determined to be that at which the desired degree of crimp will be attained, and it is at this position of the gate that the crimping of the fibers is done.

Referring back to FIGURE 1 for the actual operation of the improved crimper apparatus of our invention, the following explanation will be helpful. However, it is to be understood that the explanation does not limit in any way the operation of our invention.

The textile fibers 1 to be crimped are forced into the stuffing box by the action of the crimper rolls 2. As the fibers proceed through the stuffing box, the actuator 8 applies pressure to the gate 7 through clevis arrangement 9-. Such pressure forces the gate down into position 10. While the gate 10 is depressed, the uncrimped fibers cannot leave the stuffing box, and as a result, when more fibers are brought into the stufiing box they are forced together, backed up, and crimped. As additional uncrimped fibers are introduced into the stufling box, the fibers are forced into a smaller area, thereby increasing the number of crimps per inch of fiber length. When the fibers have been crimped to the desired degree, they will exit under the depressed gate and out of the stuffing box. When the entire amount of fibers to be crimped in any one particular crimping'operation has left the stuffing box, the actuator reduces the pressure exerted on the gate to zero, and the gate then returns to position 7.

The following table will serve to illustrate more fully the superior results we obtain when using the non-hinged gate crimper rather than the conventional hinged gate crimper. It is again to be understood that this in only an example of obtainable results and in no way limits the invention.

In the table, before refers to crimping done before the non-hinged gate of our invention had been installed; in other words, crimping was done with a conventional hinged gate. After refers to crimping done after installation of the non-hinged gate. Both tests were run on the same stuffing box type crimper and under identical conditions. The yarn crimped in these experiments was a polyester fiber, commercially available as Kodel. The gate was made of stainless steel and had the configuration as shown in FIGURE 2. Furthermore, the gate was 9 inches long with an extension of 2 inches beyond the point where the actuator force was applied.

The above-listed 25,155 pounds of polyester yarn were rejected because of lack of filling power due to poor crimp uniformity. As can readily be seen from the above table, incorporation of non-hinged gate in the crimping machine produced results far superior than those obtained when using the hinged gate.

A further test conducted on the same crimping machine and employing an identical non-hinged gate revealed zero percent rejects for 507,187 pounds of crimped polyester yarn produced.

Regarding the advantages of our invention over the cdimping machines now in use, crimp uniformity is greatly improved with the non-hinged gate due to the elimination of a hinge that may act as a snag point and cause a nonuniform restriction of the fibers as they proceed through the chamber. The non-hinged gate assumes a gentle, smooth curve rather than a straight, abrupt inclination, thus allowing a more uniform passage of fibers through the chamber and thereby increasing crimp uniformity. Due to a more uniform passage of the yarn through the chamber, the power required to turn the crimper rolls is reduced. Also, where pressure is contained in the chamber, higher pressure than now possible may be contained in, the chamber since there is no hinge leakage.

Although our invention has been described in' considerable detail with reference to certain preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described .hereinabove and as defined in the appended claims.

Weclaim:

1. An apparatus for crimping the filaments of a moving strand of textile fibers comprising:

(a) a stuffing box having a crimping chamber defined by a plurality of walls including a top wall, and having entrance and exit openings for directing the moving fibers through said chamber;

(b) said top wall being formed from a single member having a rigid first portion adjacent to the entrance opening and a flexible second portion formed as an integral extension of said first portion, extending to a location adjacent said exit opening, and varying in cross-section along the direction of fiber movement through the chamber; and

(0) means for deflecting said second portion in a gentle curve toward the moving strand of fibers in said chamber to constrict the chamber .to the movement of fibers therethrough.

2. An apparatus for crimping the filaments of a moving strand of textile fibers comprising:

(a) a stuffing box having a crimping chamber defined by a plurality of walls including a top wall, and having entrance and exit openings for directing the moving fibers through said chamber;

(b) said top wall being formed from a single member having a rigid first portion extending between said opening along the direction of feed and having integrally formed therewith a flexible second portion fixed at each end of saidfirst portion; and

(c) means for deflecting said second portion in a gentle. curve toward the moving strand of fibers and having its contact with said flexible second portion substantially midway between said fixed ends.

6 3. An apparatus for crimping the filaments of a movtached thereto at a point intermediate and substaning strand of textile fibers comprising: tially removed from both the terminal end thereof (a) a stutfiing box having a crimping chamber defined and the point of connection to said first portion.

by a plurality of Walls including a top wall, and having entrance and exit openings for directing the mov- 5 References Cted ing fibers through said chamber; UNITED STATES PATENTS (b) said top Wall being formed from a single member 2 008 11/1954 Upton et a1 28 72 having a rigid first portion adjacent to the entrance 2:763:898 9/1956 Sammons 2 19 66 opening and a flexible second portion formed as an u integral extension of said first portion extending in 10 FOREIGN PATENTS the direction of the movement of the fibers through 1,351,973 12/ 1963 F the chamber and terminating at a location adjacent 690,063 4/1953 G t B i i to said exit opening; and (c) means for deflecting said second portion in a gen- MERVIN STEIN, Primary Exammertle curve toward the moving strand of fibers and at- 15 I. C. WADDEY, Assistant Examiner. 

1. AN APPARATUS FOR CRIMPING THE FILAMENTS OF A MOVING STRAND OF TEXTILE FIBERS COMPRISING: (A) A STUFFING BOX HAVING A CRIMPING CHAMBER DEFINED BY A PLURALITY OF WALLS INCLUDING A TOP WALL, AND HAVING ENTRANCE AND EXIT OPENINGS FOR DIRECTING THE MOVING FIBERS THROUGH SAID CHAMBER; (B) SAID TOP WALL BEING FORMED FROM A SINGLE MEMBER HAVING A RIGID FIRST PORTION ADJACENT TO THE ENTRANCE OPENING AND A FLEXIBLE SECOND PORTION FORMED AS AN INTEGRAL EXTENSION OF SAID FIRST PORTION, EXTENDING TO A LOCATION ADJACENT SAID EXIT OPENING, AND VARYING IN CROSS-SECTION ALONG THE DIRECTION OF FIBER MOVEMENT THROUGH THE CHAMBER; AND (C) MEANS FOR DEFLECTING SAID SECOND PORTION IN A GENTLE CURVE TOWARD THE MOVING STRAND OF FIBERS IN SAID CHAMBER TO CONSTRICT THE CHAMBER TO THE MOVEMENT OF FIBERS THERETHROUGH. 